Adjustment method of dot printing positions and a printing apparatus

Abstract

In a complimentary printing by bi-directional scanning of a head or by a plurality of heads, a plurality of patterns in which a print start timing is shifted by a predetermined amount are printed with respect to a reference dot, e.g. formed by the forward scan of the bi-directional scanning or by one of the plurality heads. In these patterns, an area factor by the dots formed by printing of the patterns is designed to be varied depending upon shifting amount. An average density is read from each of the plurality of patterns, optically. The timing at which the maximum one among average densities read from the patterns is obtained, can be set as the printing registration condition. Further, a processing including a coarse adjustment to a fine adjustment is performed in a series of algorithm. By these processings, printing registration between a forward and a reverse scan of a print head or printing registration between a plurality of print heads in a printing apparatus can be performed simply and with high accuracy, without operating by a user.

What is claimed is:  
     
       1. A printing registration method for performing a processing for performing a printing registration in a first printing and a second printing with respect to a printing apparatus for performing printing an image by said first printing and said second printing with predetermined conditions of a dot forming position on a printing medium by using a printing head, said method comprising the steps of: 
       forming a plurality of patterns respectively having optical characteristics corresponding to a plurality of shifting amounts, the plurality of patterns being patterns formed by said first printing and second printing by using said print head, and said plurality of patterns being formed respectively corresponding to the plurality of shifting amounts of relative printing positions of said first printing and said second printing;  
       measuring the optical characteristics for each of the plurality of patterns formed by said pattern forming step;  
       acquiring adjustment value of dot forming position conditions between said first printing and said second printing on the basis of the optical characteristics of respective of the plurality of patterns measured by said measuring step; and  
       acquiring the adjustment value used for performing printing by executing plural times said pattern forming step, said measuring step and said adjustment value acquiring step for every different dot position registration accuracy.  
     
     
       2. A printing registration method as claimed in  claim 1 , wherein said adjustment value used for printing acquiring step includes a coarse adjustment step to be performed with every one dot accuracy and a fine adjustment step to be performed within less than one dot accuracy and acquires said adjustment value used for printing by performing said fine adjustment after said coarse adjustment or by performing said coarse adjustment after said fine adjustment. 
     
     
       3. A printing registration method as claimed in  claim 1 , wherein said first printing and said second printing include at least one among a printing by a forward scan and a reverse scan respectively upon performing printing by bi-directionally scanning said printing head with respect to said printing medium, a printing being a printing by a first print head and a printing by a second printing among a plurality of said print heads, in a direction in which said first printing head and said second printing head are relatively scanned respect to said printing medium, and a printing being a printing by a first print head and a printing by a second printing head among a plurality of printing heads, in a direction different from the direction in which said first printing head and said second printing head are relatively scanned with respect to said printing medium. 
     
     
       4. A printing registration method as claimed in  claim 1 , wherein said adjustment value acquiring step derives said adjustment value by calculation using continuous values on the basis of optical characteristics data obtained from said measuring step by using a linear approximation or a polynomial approximation. 
     
     
       5. A printing registration method as claimed in  claim 1 , wherein said adjustment value acquiring step has a step for calculating a printing registration condition, including also a printing position parameter of a pitch smaller than said printing registration condition or a printing position parameter different from said printing registration condition. 
     
     
       6. A printing registration method as claimed in  claim 1 , wherein said pattern forming step performs a pattern formation in a pitch looser than a pitch of the printing position capable of controlling the printing apparatus. 
     
     
       7. A printing registration method as claimed in  claim 1 , wherein, in said pattern forming step, the dots formed by said first printing and the dots by said second printing are arranged, and relative positional relationship of said dots is varied corresponding to said plurality of shifting amounts to vary a ratio of said dots covering the printing medium, thereby to form said plurality of patterns having optical characteristics corresponding to said shifting amounts. 
     
     
       8. A printing registration method as claimed in  claim 1 , wherein said measuring step has a step of measuring said optical characteristics by using an optical sensor, and further comprising a step for performing calibration for said optical sensor when using said optical sensor. 
     
     
       9. A printing registration method as claimed in  claim 8 , wherein said calibration step has a step for forming patterns for performing said calibration, a step for reading out said patterns by said optical sensor and a step for performing said calibration in response to said reading out step. 
     
     
       10. A printing registration method as claimed in  claim 1 , wherein said measuring step measures said optical characteristics using an optical sensor and wherein, in response to one of said optical sensor and a color tone of printing agent being used for the formation of said patterns, the other one is selected. 
     
     
       11. A printing registration method as claimed in  claim 10 , wherein selection of color tones of said printing agent is performed in response to optical spectrum characteristics of said optical sensor. 
     
     
       12. A printing registration method as claimed in  claim 1 , wherein the printing registration is performed with respect to the printing apparatus using a first printing head and a second printing head which are arranged in parallel in said scanning direction, on said first printing head a plurality of printing elements for imparting printing agent to said printing medium being arranged at spacing equally to in-line in a direction different from said scanning direction, thereby performing said first printing, and on said second printing head a plurality of printing elements for imparting the printing agent to said printing medium being arranged at spacing equally to in-line in a direction different from said scanning direction, thereby performing said second printing. 
     
     
       13. A printing registration method as claimed in  claim 12 , wherein the printing head for performing said first printing is a printing head using at least one printing agent of, and the printing head for performing said second printing is a print head using a plurality of printing agents of color tones among which at least one color tone is different from the color tone of said printing agent used by said first printing head. 
     
     
       14. A printing registration method as claimed in  claim 13 , wherein the printing head for performing said first printing is a print head using a black printing agent, and the print head performing said second printing is a printing using cyan, magenta and yellow printing agents, and an optical sensor has a light-emitting portion of a red light or an infrared light, and wherein to said black and said cyan printing agents are selected corresponding to said light-emitting portion to contribute to said printing registration. 
     
     
       15. A printing registration method as claimed in  claim 1 , further comprising a step for forming a confirming pattern after the processing for said printing registration. 
     
     
       16. A printing registration method as claimed in  claim 1 , further comprising a step for interrupting the processing for performing said printing registration, in a case that any error occurs during said processing. 
     
     
       17. A printing registration method as claimed in  claim 16 , further comprising a step for performing or expediting a processing for other executable printing registration during said interruption. 
     
     
       18. A printing registration method as claimed in  claim 17 , wherein the processing for said other printing registration includes a processing using means for performing adjustment for said printing registration by a manual operation. 
     
     
       19. A printing registration method as claimed in  claim 1 , wherein processing for said printing registration is performed respectively corresponding to plural modes carried by said printing apparatus. 
     
     
       20. A printing registration method as claimed in  claim 19 , wherein all of said respective processings for said printing registration are performed in the lump for all modes carried by said printing apparatus. 
     
     
       21. A printing registration method as claimed in  claim 19 , wherein said plural modes are printings performed by varying at least one of conditions of said scanning speed, printing resolution and size of printing dots. 
     
     
       22. A printing registration method as claimed in  claim 21 , wherein said printing head is a head performing a printing by ejecting an ink, and said plural modes are printings performed by varying at least one of ejecting speed of said ink, ejecting angles and said conditions. 
     
     
       23. A printing registration method as claimed in  claim 1 , wherein said printing head is a head for performing a printing by ejecting an ink. 
     
     
       24. A printing registration method as claimed in  claim 23 , wherein performing a recovery operation for making an ejecting state of said ink better before performing said processing for said printing registration. 
     
     
       25. A printing registration method as claimed in  claim 24 , wherein, corresponding to an elapsed time from recovery operation previously performed, presence of performing said recovery operation or contents of said recovery operation is decided before performing said processing for said printing registration. 
     
     
       26. A printing registration method as claimed in  claim 24 , wherein, corresponding to ejecting amounts after recovery operation previously performed, presence of performing said recovery operation or contents of said recovery operation is decided before performing said processing for said printing registration. 
     
     
       27. A printing registration method as claimed in  claim 23 , wherein said printing head has heating elements for generating thermal energy to make the ink to film-boil as an energy used for ejecting the ink. 
     
     
       28. A printing registration method as claimed in  claim 1 , wherein said measuring step acquires a plurality of data by measuring plural times optical characteristics with positions made different with respect to each of a plurality of patterns formed by said pattern forming step, and said adjustment value acquiring step derives optical characteristics of respective patterns from said plurality of data obtained with respect to each of said plurality of patterns and acquires an adjustment value of dots forming position conditions between said first printing and said second printing on the basis of said optical characteristics, and, said method further comprising the steps of judging per each of said plurality of patterns that said patterns are formed in a state not suitable for acquiring said adjustment value from said plurality of data obtained per each of said plurality of patterns, and eliminating patterns formed in a state not suitable for acquiring said adjustment value from the processing of said adjustment value acquiring step. 
     
     
       29. A printing registration method for performing a processing for performing a printing registration in a first printing and a second printing with respect to a printing apparatus for performing printing an image by said first printing and said second printing with predetermined conditions of a dot forming position on a printing medium by using a printing head, said method comprising the steps of: 
       forming patterns used for said processing by said first printing and said second printing;  
       acquiring adjustment value of dot forming position conditions on the basis of said patterns; and  
       performing said first and second printing with every different dot position registration accuracy and acquiring an adjustment value used for performing said printing.  
     
     
       30. A printing registration method as claimed in  claim 29 , wherein it is possible to form plural kinds of patterns having different properties as said patterns. 
     
     
       31. A printing registration method for performing a processing for performing a printing registration in a first printing and a second printing with respect to a printing apparatus for performing printing an image by said first printing and said second printing with predetermined conditions of a dot forming position on a printing medium by using a printing head, said method comprising the steps of: 
       forming patterns used for said processing by said first printing and said second printing;  
       acquiring adjustment value of dot forming position conditions on the basis of said patterns; and  
       performing said first and second printing with every different dot position registration accuracy and acquiring an adjustment value used for performing said printing,  
       wherein at least one among said plural kinds of patterns is a pattern for measuring optical characteristics of said patterns, and at least the other one is a pattern for measuring formation positions of printing dots with the eye.  
     
     
       32. A printing registration method for performing a processing for performing a printing registration in a first printing and a second printing with respect to a printing apparatus for performing printing image by said first printing and said second printing with predetermined conditions of a dot forming on a printing medium by using a printing head, said method comprising the steps of: 
       forming a plurality of patterns respectively having optical characteristics corresponding to a plurality of shifting amounts, the plurality of patterns being patterns formed by said first printing and said second printing by using said print head, and said plurality of patterns being formed respectively corresponding to the plurality of shifting amounts of relative printing positions of said first printing and said second printing;  
       measuring a plurality of data by measuring plural times optical characteristics with positions made different with respect to each of said plurality of patterns formed by said pattern forming step;  
       deriving optical characteristics of respective patterns from said plurality of data obtained per each of said plurality of patterns and acquiring adjustment value of dots forming position conditions between said first printing and said second printing on the basis of said optical characteristics; and  
       making judgment per each of said plurality of patterns that said patterns are formed in a state not suitable for acquiring said adjustment value from said plurality of data obtained per each of said plurality of patterns and eliminating patterns formed in a state not suitable for acquiring said adjustment value from a processing of said value adjustment step.  
     
     
       33. A printing registration method as claimed in  claim 32 , wherein said adjustment value acquiring step calculates an average value of said plurality of data and defines it as the optical characteristic relative to said pattern. 
     
     
       34. A printing registration method as claimed in  claim 32 , wherein said judgment'step judges presence of a density unevenness developed in said pattern from said plurality of data as a state not suitable for acquiring said adjustment value. 
     
     
       35. A printing registration method as claimed in  claim 32 , wherein said judgment step judges that said pattern is formed in a state not suitable for acquiring said judgment value when a difference between a maximum value and a minimum value of said plurality of data is larger than a predetermined value. 
     
     
       36. A printing registration method as claimed in  claim 32 , wherein said pattern forming step forms patterns more than necessary in minimum for said printing registration, and further comprising a step for supplying the optical characteristics relative to other patterns to a step for acquiring said adjustment value acquiring step when presence of patterns formed in a state not suitable for acquiring said adjustment value is judged. 
     
     
       37. A printing registration method as claimed in  claim 32 , further comprising a step for accepting a manual adjustment for the printing registration when optical characteristics relative to the number of said patterns sufficient enough to perform said adjustment acquiring step by said elimination is not obtained. 
     
     
       38. A printing registration method as claimed in  claim 32 , further comprising a step for performing at least reformation and remeasurement of said patterns when judgment is made that said patterns are formed in a state not suitable for acquiring said adjustment value. 
     
     
       39. A printing registration method as claimed in  claim 32 , wherein said first printing and said second printing include at least one among a printing by a forward scan and a reverse scan respectively upon performing printing by bi-directionally scanning said printing head with respect to said printing medium, a printing being a printing by a first print head and a printing by a second printing among a plurality of said print heads, in a direction in which said first printing head and said second printing head are relatively scanned respect to said printing medium, and a printing being a printing by a first print head and a printing by a second printing head among a plurality of printing heads, in a direction different from the direction in which said first printing head and said second printing head are relatively scanned with respect to said printing medium. 
     
     
       40. A printing registration method as claimed in  claim 32 , wherein said adjustment value acquiring step derives said adjustment value by calculation using continuous values on the basis of the optical characteristics data obtained from said measuring step by using a linear approximation or a polynomial approximation. 
     
     
       41. A printing registration method as claimed in  claim 32 , wherein said pattern forming step performs a pattern formation in a pitch looser than a pitch of the printing position capable of controlling the printing apparatus. 
     
     
       42. A printing registration method as claimed in  claim 32 , wherein, in said pattern forming step, the dots formed by said first printing and the dots by said second printing are arranged, and relative positional relationship of said dots is varied corresponding to said plurality of shifting amounts to vary a ratio of said dots covering the printing medium, thereby to form said plurality of patterns having optical characteristics corresponding to said shifting amounts. 
     
     
       43. A printing registration method as claimed in  claim 32 , wherein the printing registration is performed with respect to the printing apparatus using a first printing head and a second printing head which are arranged in parallel in said scanning direction, on said first printing head a plurality of printing elements for imparting printing agent to said printing medium being arranged at spacing equally to in-line in a direction different from said scanning direction, thereby performing said first printing, and on said second printing head a plurality of printing elements for imparting the printing agent to said printing medium being arranged at spacing equally to in-line in a direction different from said scanning direction, thereby performing said second printing. 
     
     
       44. A printing registration method as claimed in  claim 43 , wherein the printing head for performing said first printing is a printing head using at least one printing agent, and the printing head for performing said second printing is a print head using a plurality of printing agents of color tones among which at least one color tone is different from the color tone of said printing agent used by said first printing head. 
     
     
       45. A printing registration method as claimed in  claim 32 , wherein said printing head is a head for performing a printing by ejecting an ink. 
     
     
       46. A printing registration method as claimed in  claim 45 , wherein said printing head has heating elements for generating thermal energy to make the ink to film-boil as an energy used for ejecting the ink. 
     
     
       47. A printing apparatus for performing printing an image by a first printing and a second printing with predetermined conditions of a dot forming position on a printing medium by using a printing head, comprising: 
       means for forming a plurality of patterns respectively having optical characteristics corresponding to a plurality of shifting amounts, the plurality of patterns being patterns formed by said first printing and second printing by using said print head, and said plurality of patterns being formed respectively corresponding to the plurality of shifting amounts of relative printing positions of said first printing and said second printing;  
       means for measuring the optical characteristics for each of the plurality of patterns formed by said pattern forming means;  
       means for acquiring adjustment value of dot forming position conditions between said first printing and said second printing on the basis of the optical characteristics of respective of the plurality of patterns measured by said measuring means; and  
       means for acquiring the adjustment value used for performing printing by executing plural times of operations of said pattern forming means, said measuring means and said adjustment value acquiring means for every different dot position registration accuracy.  
     
     
       48. A printing apparatus for performing printing an image by a first printing and a second printing with predetermined conditions of a dot forming position on a printing medium by using a printing head, comprising: 
       means for forming patterns used for processing of printing registration by said first printing and said second printing and for acquiring adjustment value of dot forming position conditions on the basis of said patterns;  
       and wherein operations by said means are performed with every different dot position registration accuracy so that an adjustment value used for performing said printing is acquired.  
     
     
       49. A printing apparatus for performing printing image by said first printing and a second printing with predetermined conditions of a dot forming on a printing medium by using a printing head, comprising: 
       means for forming a plurality of patterns respectively having optical characteristics corresponding to a plurality of shifting amounts, the plurality of patterns being patterns formed by said first printing and said second printing by using said print head, and said plurality of patterns being formed respectively corresponding to the plurality of shifting amounts of relative printing positions of said first printing and said second printing;  
       means for measuring a plurality of data by measuring plural times the optical characteristics with positions made different with respect to each of said plurality of patterns formed by said pattern forming means;  
       means for deriving the optical characteristics of respective patterns from said plurality of data obtained per each of said plurality of patterns and acquiring adjustment value of dots forming position conditions between said first printing and said second printing on the basis of said optical characteristics; and  
       means for making judgment per each of said plurality of patterns that said patterns are formed in a state not suitable for acquiring said adjustment value from said plurality of data obtained per each of said plurality of patterns and eliminating patterns formed in a state not suitable for acquiring said adjustment value from a processing of said value adjustment means.  
     
     
       50. A printing system provided with a printing apparatus for performing printing an image by a first printing and a second printing with predetermined conditions of a dot forming position on a printing medium by using a printing head, and a host apparatus for supplying an image data to said printing apparatus, comprising: 
       means for forming a plurality of patterns respectively having optical characteristics corresponding to a plurality of shifting amounts, the plurality of patterns being patterns formed by said first printing and second printing by using said print head, and said plurality of patterns being formed respectively corresponding to the plurality of shifting amounts of relative printing positions of said first printing and said second printing;  
       means for measuring the optical characteristics for each of the plurality of patterns formed by said pattern forming means;  
       means for acquiring adjustment value of dot forming position conditions between said first printing and said second printing on the basis of the optical characteristics of respective of the plurality of patterns measured by said measuring means; and  
       means for acquiring the adjustment value used for performing printing by executing plural times of operations of said pattern forming means, said measuring means and said adjustment value acquiring means for every different dot position registration accuracy.  
     
     
       51. A printing system provided with a printing apparatus for performing printing an image by a first printing and a second printing with predetermined conditions of a dot forming position on a printing medium by using a printing head, and a host apparatus for supplying an image data to said printing apparatus, comprising: 
       means for forming patterns used for a processing of printing registration by said first printing and said second printing and for acquiring adjustment value of dot forming position conditions on the basis of said patterns; and  
       wherein operations by said means are performed with every different dot position registration accuracy so that an adjustment value used for performing said printing is acquired.  
     
     
       52. A printing system provided with a printing apparatus for performing printing image by a first printing and a second printing with predetermined conditions of a dot forming on a printing medium by using a printing head, and a host apparatus for supplying an image data to said printing apparatus, comprising: 
       means for forming a plurality of patterns respectively having optical characteristics corresponding to a plurality of shifting amounts, the plurality of patterns being patterns formed by said first printing and said second printing by using said print head, and said plurality of patterns being formed respectively corresponding to the plurality of shifting amounts of relative printing positions of said first printing and said second printing;  
       means for measuring a plurality of data by measuring plural times the optical characteristics with positions made different with respect to each of said plurality of patterns formed by said pattern forming means;  
       means for deriving the optical characteristics of respective patterns from said plurality of data obtained per each of said plurality of patterns and acquiring adjustment value of dots forming position conditions between said first printing and said second printing on the basis of said optical characteristics; and  
       means for making judgment per each of said plurality of patterns that said patterns are formed in a state not suitable for acquiring said adjustment value from said plurality of data obtained per each of said plurality of patterns and eliminating patterns formed in a state not suitable for acquiring said adjustment value from a processing of said value adjustment means.  
     
     
       53. A storage medium which is connected to an information processing apparatus and a program stored in which is readable by the information processing apparatus, said program being for making a printing system to perform a printing registration method for performing a processing for performing a printing registration in a first printing and a second printing with respect to a printing apparatus for performing printing an image by said first printing and said second printing with predetermined conditions of a dot forming position on a printing medium by using a printing head, said method comprising the steps of: 
       forming a plurality of patterns respectively having optical characteristics corresponding to a plurality of shifting amounts, the plurality of patterns being patterns formed by said first printing and second printing by using said print head, and said plurality of patterns being formed respectively corresponding to the plurality of shifting amounts of relative printing positions of said first printing and said second printing;  
       measuring the optical characteristics for each of the plurality of patterns formed by said pattern forming step;  
       acquiring adjustment value of dot forming position conditions between said first printing and said second printing on the basis of the optical characteristics of respective of the plurality of patterns measured by said measuring step; and  
       acquiring the adjustment value used for performing printing by executing plural times said pattern forming step, said measuring step and said adjustment value acquiring step for every different dot position registration accuracy.  
     
     
       54. A storage medium which is connected to an information processing apparatus and a program stored in which is readable by the information processing apparatus, said program being for making a printing system to perform a printing registration method for performing a processing for performing a printing registration in a first printing and a second printing with respect to a printing apparatus for performing printing an image by said first printing and said second printing with predetermined conditions of a dot forming position on a printing medium by using a printing head, said method comprising the steps of: 
       forming patterns used for said processing by said first printing and said second printing;  
       acquiring adjustment value of dot forming position conditions on the basis of said patterns; and  
       performing said first and second printing with every different dot position registration accuracy and acquiring an adjustment value used for performing said printing.  
     
     
       55. A storage medium which is connected to an information processing apparatus and a program stored in which is readable by the information processing apparatus, said program being for making a printing system to perform a printing registration method for performing a processing for performing a printing registration in a first printing and a second printing with respect to a printing apparatus for performing printing image by said first printing and said second printing with predetermined conditions of a dot forming on a printing medium by using a printing head, said method comprising the steps of: 
       forming a plurality of patterns respectively having optical characteristics corresponding to a plurality of shifting amounts, the plurality of patterns being patterns formed by said first printing and said second printing by using said print head, and said plurality of patterns being formed respectively corresponding to the plurality of shifting amounts of relative printing positions of said first printing and said second printing;  
       measuring a plurality of data by measuring plural times the optical characteristics with positions made different with respect to each of said plurality of patterns formed by said pattern forming step;  
       deriving the optical characteristics of respective patterns from said plurality of data obtained per each of said plurality of patterns and acquiring adjustment value of dots forming position conditions between said first printing and said second printing on the basis of said optical characteristics; and  
       making judgment per each of said plurality of patterns that said patterns are formed in a state not suitable for acquiring said adjustment value from said plurality of data obtained per each of said plurality of patterns and eliminating patterns formed in a state not suitable for acquiring said adjustment value from a processing of said value adjustment step.